ABSTRACT Every day thousands of children in the United States are coerced into commercial sex, including prostitution, pornography, and stripping. While the perception is often that commercial sexual trafficking and exploitation of minors (CSTEM) is an urban problem is increasingly happening in rural communities across the U.S. CSTEM often remains unseen in rural communities, due in part to a lack of specific trafficking or exploitation data recorded in rural communities, and because CSTEM in rural settings looks very different than in an urban setting, contributing to under-recognition. In these areas, many children are trafficked by a family member or family friend in or near their own community, with 60% of familial trafficking occurring in rural areas. The most common motivator for familial trafficking is the funding of illicit drug use and consequently, the tragedy of the opioid crisis has also caused an increase in CSTEM in rural areas. While the impact of CSTEM is growing, the public health response has focused on urban areas and the emphasis and funding for rural areas experiencing trafficking has not kept pace. Unlike urban areas, the vast majority of professionals who come into contact with youth at risk for CSTEM in rural areas, including educators and healthcare providers, often have limited or no training or experience that prepares them to identify or respond to sexually exploited youth. The unique presentations of CSTEM in rural areas and the needs for specific training for rural providers have created a critical gap in addressing CSTEM in the U.S. This Phase I SBIR project will address this critical gap by developing and testing AppDelivered Training to Identify and Report the Commercial Sexual Exploitation of Youth in Rural Settings (CSTEM Rural). CSTEM Rural is a customized app-delivered interactive multimedia training and resource for rural professionals in education and healthcare fields to assist them in identifying and responding to victims and those at risk of CSTEM in their rural areas. Phase I will test feasibility by: 1) conducting formative research interviews; 2) developing two modules of a general curriculum for county health department personnel; 3) developing and testing product prototypes of a mobile and desktop app that provide a visually engaging multimedia interactive set of training modules for those in the health field with curriculum customization by profession/position; and (c) a resource center that provides a set of resources to help respond to at risk youth that will meet their including geographically specific referrals for victim assistance; and 4) conducting a pilot evaluation in which the prototype is used by public health department staff to assess impact of the prototype on CSTEM skills, knowledge and attitudes. Phase II will complete development of the health department track, add the complete education curriculum track; complete the resource database with resources from across the United States; and implement a large scale evaluation study of the effectiveness of the entire product on increasing identification and referral of rural youth who are or who are at risk of sexual exploitation and sex trafficking.